Pattern control for tufting machine attachments

ABSTRACT

A pattern control for tufting machine yarn feed roller pattern attachments which provide controlled yarn feed to individual needles for varying pile height according to a pattern design. The pattern design is painted on a transparent film placed on an internally lighted hollow drum. The drum includes teeth on its periphery at the ends and is supported on a cradle including toothed wheels intermeshing with the teeth on the drum. The wheels are driven so that the drum is rotated in timed relation with the tufting machine. As this occurs, light passes through the drum or is blocked out by the design. The light passing through strikes rows of photocells and thereby trigger clutches in the feed rollers.

United States Patent Ingham et al.

Dec. 2, 1975 1 1 PATTERN CONTROL FOR TUFTING MACHINE ATTACHMENTS [75] lnventors: David Ingham, Blackburn; Edward C. Lear, Lancaster, both of England [73] Assignee: The Singer Company, New York,

[22] Filed: Dec. 18, 1974 [21] Appl. No.: 534,013

[52] U.S. Cl 112/79 A [51] Int. Cl. DOSC 15/26 [58] Field of Search 112/79 A, 79 R, 78

[56] References Cited UNITED STATES PATENTS 3,103,187 9/1973 Hammel 112/79 A 3,272,163 9/1966 Erwin et al. 112/79 A 3,435,787 4/1969 Short 112/79 A 3,489,326 1/1970 Singleton 112/79 A Primary E.\'aminerH. Hampton Hunter Attorney, Agent, or FirmRobert E. Smith; Edward 1.. Bell; Alan Ruderman [57] ABSTRACT A pattern control for tufting machine yarn feed roller pattern attachments which provide controlled yarn feed to individual needles for varying pile height according to a pattern design. The pattern design is painted on a transparent film placed on an internally lighted hollow drum. The drum includes teeth on its periphery at the ends and is supported on a cradle including toothed wheels intermeshing with the teeth on the drum. The wheels are driven so that the drum is rotated in timed relation with the tufting machine, As this occurs, light passes through the drum or is blocked out by the design. The light passing through strikes rows of photocells and thereby trigger clutches in the feed rollers.

4 Claims, 4 Drawing Figures US. Patent Dec. 2, 1975 Sheet 1 of ,2 3,922,979

Fig. I

U.S. Patent D66. 2, 1975 Sheet 2 on 3,922,979

PATTERN CONTROL FOR TUFTING MACHINE ATTACHMENTS BACKGROUND OF THE INVENTION This invention relates to a control for-pattern attachments for tufting machines and more particularly to a control apparatus for mounting and scanning a pattern.

A pattern attachment for a tufting machine provides controlled yarn feed to individual needles thereby creating in the tufted fabric a variety of pile heights and control of contrasts. One type of tufting machine pattern attachments consists of two or three rows of yarn feed rollers with a clutch mechanism that regulates the speed of each roller, thus regulating the amount of yarn fed and the pile height which forms the tufted design. Pattern attachments of this type are disclosed in US. Pat. ofHammel, No. 3,103,187 and U.S. Pat. of Singleton, No. 3,489,326. In these and other embodiments the pattern attachment is controlled by a pattern control which may be of the photo-electric type forming the subject matter of the aforesaid Hammel patent. This control comprises an internally lighted translucent or transparent drum carrying a translucent or transparent film on which the desired pattern design is painted. The drum is rotated in synchronism with the tufting machine and the light either passes through or is blocked out by the design. The light passing through the design strikes rows of photocells which in turn transmit electronic signals that activate the appropriate clutches of the yarn feed roller pattern attachment. A later version of the control provides for disposing of the pattern device in a console remote from the tufting machine.

A drum of the prior art control is supported for rotation on a rod or shaft journalled in a pair of end plates. Since the light source comprises a lamp mounted within the drum, replacement or adjustment of the lamp requires disassembly of the drum. Furthermore, since the photocells, in order to have their maximum response to the light source, are mounted in very close proximity to the surface of the drum, the drum must be removed from the console in order to provide access to the photocells. Access to other components also requires disassembly and removal of the drum. Additionally, since the drums inherently have some eccentricity, rotation of the drum causes variations in the gap between the photocells and the drum, and consequently the pattern. Since the intensity of the light striking the photocells thereby varies, a loss of pattern definition in the tufted fabric produced results.

SUMMARY OF THE INVENTION The present invention overcomes these deficiencies of the prior art by providing a pattern control of the above type in which the pattern drum is centerless and rotatably mounted at the periphery of its ends on a cradle which drives the drum. The drum preferably has a ring of external teeth at each end and the cradle comprises a plurality of wheels having external teeth meshing with the teeth on the drum. The wheels are driven in timed relation with the tufting machine so as to thereby drive the drum. Since the shaft or rod is eliminated, the drum is constructed without end plates. Thus, the lamp may be removed and replaced without disassembling the drum. Furthermore, access to the photocells or other components is had by the drum simply being lifted off the cradle and removed without any I disassembly. Moreover, errors due to eccentricity of the drum surface are minimized since the drum essentially rotates on its periphery.

Accordingly, it is a primary object of the present invention to provide an improved pattern control mechanism for tufting machine pattern attachments having greater accuracy and accessability for maintenance.

It is another object of this invention to provide an improved photo-electric pattern scanning control for tufting machine pattern attachments including a rotating internally lighted pattern supporting drum having a centerless mounting.

BRIEF DESCRIPTION OF THE DRAWING Other objects and advantages of the invention will best be understood upon reading the following detailed description of the invention with the accompanying drawings, in which:

FIG. 1 is a composite view partly in vertical section and partly in elevation illustrating a fragment of a tufting machine having a pattern attachment and a pattern control console for the attachment;

FIG. 2 is a fragmentary front elevational view of the control console of FIG. 1 with parts broken away and in section to illustrate the device;

FIG. 3 is a fragmentary perspective view of the photo-electric pattern scanning portion of the control console of FIG. 1; and

FIG. 4 is a fragmentary vertical sectional view taken substantially along line 4--4 of FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, there is illustrated in FIG. 1 a tufting machine having a frame comprising a bed 12 and a head 14 disposed above the bed 12. The bed 12 includes a bed plate 16 across which a fabric F is adapted to be fed by a pair of feed rolls l8 and takeoff rolls 20.

Mounted in the head 14 for vertical reciprocation is a push rod 22 to the lower end of which is received a needle bar 24 which in turn carries a plurality of needles 26 that are adapted to penetrate the fabric F on the bed plate 16 upon reciprocation of the needle bar 24 and to project loops of yarn there through. Endwise reciprocation is imparted to the push rod 22 and thus the needle bar 24 and needles 26 by a link 28 which is pivotally connected at its lower end to the push rod 22 and at its upper end to an eccentric 30 on the driven rotary main shaft 32 that is journalled longitudinally of the head 14. While a plurality of push rods 22, links 28, cccentrics 30 and needles 26 are normally provided along the main shaft 32, only one set thereof is illustrated in the drawings.

Beneath the bed plate 16 there is journalled an oscillating looper shaft 34 which is arranged parallel to the main shaft 32 and which carries a looper 36. Each looper 36 cooperates with a needle 26 to seize a loop of yarn presented thereby and hold the same as the needle is withdrawn on its return stroke, after which the looper retracts to release the loop. While, to simplify the disclosure, only a single looper 36 is shown, it is understood that one looper is provided for each needle in the machine.

Yarn Y is fed to the needles 26 by a pattern attachment generally indicated at 38. The illustrated pattern attachment is of the type disclosed in the above referred to Singleton patent and is herein described only insofar as it is necessary for an understanding of thisinvention. Basically, this yarn feed roll mechanism comprises spaced modules having drive shafts 40, 42 and 44. The shafts which are rotatably supported on brackets (not shown) are each driven at a different speed in any conventional manner, for example, chains and sprockets, as described in the said Singleton patent. Rotatably mounted on each drive shaft is a plurality of respective feed roll units 46, 48 and 50. The rolls of the shafts are drivingly connected one to the other and include an electromagnetic clutch mounted within each roll for drivingly transmitting the rotational motion of the shaft to the respective roll. This allows the rolls to be driven selectively at the speed of one or the other drive shafts. The amount of yarn supplied to the needles of the tufting machine is determined by the rotational speed of the feed rolls on which the yarn strand is wound, so that with a fixed needle stroke the amount of yarn supplied to the needle determines the pile height of the pile fabric produced. To create patterned pile effects the amount of yarn fed to the individual needles may be varied by driving the feed rolls selectively at different speeds, i.e., the speed of one or the other drive shafts. The clutches are adapted to be energized by a pattern mechanism, which in accordance with this invention, is housed within a console 52 remote from the tufting machine. The clutches are individually connected electrically to the pattern mechanism by wire disposed within a conduit 54.

The console 52 is of the type illustrated in US. Pat. of Irwin et.al., No. 3,272,163 and comprises of substantially rectangular sheet metal enclosure. A base portion (only part of which is shown) rests on the floor and supports corner brackets to which a pair of sidewalls 56 and 58 and a front wall 60 are secured. The walls and the corner brackets comprise a frame for supporting the various elements of the console. Mounted in the base portion are the printed circuit switching units 62 and other conventional circuit elements not forming part of the present invention. A control panel 64 and a window 66 may be mounted in the front wall of the console. Supported substantially horizontally on the side walls 56 and 58 of the console is a partition plate 68 which separates the console switching circuits from the pattern reading elements.

Within the console secured to the plate 68 and to the frame are a pair of substantially vertical standards 70 and 72. Secured at the lower ends of the standards and supported by the plate 68 are a pair of L-shaped brackets 74 and 76. A similar pair of L-shaped brackets 78 and 80 are also secured to the standard near their upper ends. Supported on the brackets 74 and 76 and on the brackets 78 and 80 are respective photo-electric header units 82 and 84 each mounting a plurality of photocells 86 disposed in a line, there being one photocell on each header for each group of feed roll clutches. Electrical wiring (not shown) conducts current between the photocells and the switching units which function to amplify and decide which clutches to activate. Brackets 88 and 90 and brackets 92 and 94 are respectively supported at opposite ends ofthe headers 82 and 84 for supporting respective incandescent or fluorescent elongated bulbs 96 and 98 above the photocells. Electrical power is delivered to the bulbs through the respective brackets 88, 90, 92 and 94.

' Each light bulb 96 and 98 passesthrough a respective light transmitting, translucent or transparent openended drum 100 and 102 preferably composed of an acrylic material. On the periphery of each drum 100 and 102 there is mounted a respective pattern sheet 104 and 106 of translucent or transparent material and on which thedesired pattern is painted with an opaque material. The pattern control system disclosed is contemplated to be used with a three pile height pattern attachment. The pattern sheets however have the information formulated in black or clear a two state system rather than black, clear and gray a three state system. Since the three pile height attachment requires three states, the control system, in order to obtain the third state, uses two pattern drums and two pattern sheets and, of course, two separate banks of photocells, as llustrated. The pattern on the two sheets will differ somewhat from each other. Thus, the pattern on sheet 106 differs from that on sheet 104. If a two pile height attachment is used, only one drum and pattern sheet is required.

In order to support the drum for rotation in sychronism with the tufting machine, the present invention provides a cradle on which each drum is supported and rotated in centerless fashion. The cradle for the drum 100 comprises a pair of spaced shafts 108 and 110 journalled in the standards and 72. The shaft 108 is disposed below and in front of the drum while the shaft is disposed below and to the rear of the drum 100. Positioned on the shaft 108 are a pair of spaced wheels 112 and 114 having respective sets of peripheral or circumferential external teeth 116 and 118 which intermesh respectively with a ring of -external teeth 120 and 122 on the ends of the drum 100. Preferably the teeth 116, 118, 120 and 122 comprise flexible timing belts positioned respectively about the wheels 112 and l 14 and the drum 100. The wheels 112 and 114 include flanges 124 and 126 which laterally position the drum 100 on the teeth 116 and 118 for ease of assembly and for preventing shifting of the drum axially of the shaft 108. In8c a similar fashion the shaft 110 includes wheels 127 and 128 which together with the wheels 112 and 114 act as a cradle to support the drum 100. Similarly, the drum 102 is supported by wheels 130 and 132 mounted on the shaft 134 and wheels 136 and 138 mounted on shaft 140. Of course, the drum 102 includes a ring of teeth 142 and 144 located on opposite ends in a manner similar to the drum 100.

In order to drive the drums 100 and 102 in timed relationship to the tufting machine one end of each shaft 108, 110, 134 and mounts a respective pulley 146, 148, I50 and 152. Preferably each pulley may be formed with teeth for meashing with a toothed timing belt 154. The timing belt 154 is trained about the pulleys and a toothed driving wheel or gear 156. A biased tensioning or jockey pulley 158 may preferably apply tension to the belt 154'so that slippage is minimized. The drive wheel 156 is mounted on a shaft 160 of a steeper motor 162 mounted on a bracket 164 secured to the frame of the console. The stepping motor 162 is synchronized with the tuftingma'chine by means of a pulse generator (not shown) which transmits a number of pulses to the motor for each foot of tufted pile fabric fed from the tufting machine. The stepping motor rotates one revolution for a given number of pulses received. In this matter, the stepping motor and hence the drums 100 and 102 are driven in timed relationship to the tufting machine fabric feed rolls.

it should thus be understood that a pattern control for tufting machines pattern attachments is disclosed having a construction which eliminates the problems of the prior art. To replace a bulb, for example bulb 96, the bulb may be removed from the sockets in the brackets 88 and 90 and the bulb slipped out from one of the open ends of the drum 100. If a photocell is to be replaced or cleaned, or if other components must be maintained, the drum 100 may then simply be lifted off the cradle for access to the component. Replacement of the drum merely involves setting the same upon the toothed wheels. Alignment is provided by the flanges of the wheels. Thus, an improved pattern control has been devised for which protection is hereby sought.

Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to a preferred embodiment of the invention which is for purposes of illustration only and not to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.

Having thus set forth the nature of the invention, what is claimed herein is:

1. A pattern control for tufting machine pattern attachments comprising, a console remote from the tufting machine, an open ended hollow drum having a light transmitting surface mounted in the console, a pattern element having light transmitting and opaque areas mounted on the surface of the drum, a light source positioned within the drum, a plurality of photocells mounted in the console adjacent to the surface of the drum and electrically connected to the pattern attachment, a cradle for supporting the drum, said cradle comprising aa plurality of members drivingly connected to the periphery of the drum at each end, and means for rotating said members in timed relation with the tufting machine so that said pattern element moves between the light source and the photocells.

2. A pattern control as recited in claim 1 wherein said drum comprises a ring of external teeth spaced about the periphery at each end, said cradle members comprising wheels having external teeth about the periphery, at least two of said wheels intermeshing with each ring of teeth.

3. A pattern control as recited in claim 2 wherein said rings of teeth and said wheel teeth comprise timing belts positioned respectively about the periphery of the drum and wheels.

4. A pattern control as recited in claim 1 wherein said photocells are mounted on a header substantially parallel to the axis of rotation of the drum and spanning the drum, a pair of bracket members carried by the header at opposite ends of the drum, said light source comprising a lamp spanning the drum and mounted in sockets formed in said brackets. 

1. A pattern control for tufting machine pattern attachments comprising, a console remote from the tufting machine, an open ended hollow drum having a light transmitting surface mounted in the console, a pattern element having light transmitting and opaque areas mounted on the surface of the drum, a light source positioned within the drum, a plurality of photocells mounted in the console adjacent to the surface of the drum and electrically connected to the pattern attachment, a cradle for supporting the drum, said cradle comprising aa plurality of members drivingly connected to the periphery of the drum at each end, and means for rotating said members in timed relation with the tufting machine so that said pattern element moves between the light source and the photocells.
 2. A pattern control as recited in claim 1 wherein said drum comprises a ring of external teeth spaced about the periphery at each end, said cradle members comprising wheels having external teeth about the periphery, at least two of said wheels intermeshing with each ring of teeth.
 3. A pattern control as recited in claim 2 wherein said rings of teeth and said wheel teeth comprise timing belts positioned respectively about the periphery of the drum and wheels.
 4. A pattern control as recited in claim 1 wherein said photocells are mounted on a header substantially parallel to the axis of rotation of the drum and spanning the drum, a pair of bracket members carried by the header at opposite ends of the drum, said light source comprising a lamp spanning the drum and mounted in sockets formed in said brackets. 